Three projects involving structure determinations of proteins that are drug design targets. They are a bacterial cell wall synthesis enzyme (MurB) and the microsomal triglyceride transfer protein (MTP) and they remain at high priority in our laboratory. The third protein, human cytomegalovirus (HCMV) protease, is new. Each of these projects involves the use of three-dimensional structural information to aid in the design of new therapeutic agents. In each case, the goal is to inhibit a novel protein target. Each of these structure projects presents unique challenges that require the use of synchrotron radiation for data collection.